Accelerating f(T) gravity models constrained by recent cosmological data

TL;DR

This paper evaluates two f(T) gravity models that can mimic accelerated cosmic expansion, testing their consistency with recent cosmological data and exploring their distinguishability through growth factors.

Contribution

It introduces and tests two specific f(T) gravity models against extensive observational data, demonstrating their viability and potential for differentiation.

Findings

Both models fit the observational data well.

The models can emulate phantom divide crossing.

Potential to distinguish models via growth factors.

Abstract

Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an effective torsion fluid whose equation of state depend on the f(T) function entering the modified gravity Lagrangian. We focus on two particular choices for f(T) which share the nice property to emulate a phantom divide crossing as suggested by some recent data. We check their viability contrasting the predicted background dynamics to the Hubble diagram as traced by both Type Ia Supernovae (SNeIa) and Gamma Ray Bursts (GRBs), the measurement of the rate expansion H(z), the Baryon Acoustic Oscillations (BAOs) at different redshifts, and the Cosmic Microwave Background Radiation (CMBR) distance priors. Both f(T) models turn out to be in very good agreement with this large dataset so that we also investigate whether it is possible to discriminate among them relying on the different growth factors.